body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f9f9f9;
}

nav {
    background-color: #333;
    color: white;
    padding: 1rem;
    text-align: center;
}

nav a {
    color: white;
    margin: 0 10px;
    text-decoration: none;
}

.container {
    padding: 2rem;
    max-width: 800px;
    margin: auto;
    background-color: white;
    box-shadow: 0px 0px 10px rgba(0, 0, 0, 0.1);
}

h1 {
    color: #333;
}

.alert {
    padding: 1rem;
    margin-bottom: 1rem;
    border-radius: 5px;
}

.alert-success {
    background-color: #d4edda;
    color: #155724;
}

.alert-danger {
    background-color: #f8d7da;
    color: #721c24;
}

.error {
    border: 1px solid red;
}

.error-message {
    color: red;
    font-size: 0.9rem;
}

nav a.active {
    font-weight: bold;
    text-decoration: underline;
    color: yellow;
}
